You are here:
FINE PARTICULATE MATTER SOURCE ATTRIBUTION FOR SOUTHEAST TEXAS USING 14C/13C RATIOS
Citation:
Lemire, K. R., D. Allen, G. A. Klouda, AND C W. Lewis. FINE PARTICULATE MATTER SOURCE ATTRIBUTION FOR SOUTHEAST TEXAS USING 14C/13C RATIOS. JOURNAL OF GEOPHYSICAL RESEARCH 107(D22):ACH X-1 to ACH X-7, (2002).
Impact/Purpose:
The analysis of ambient air samples by X-ray fluorescence is a critical component in the interpretation of complex air quality studies. The data products generated by the XRF laboratory are therefore critical to protecting human health and the environment. Analysis of particulate matter by XRF contributes to the following outcomes:
1) By characterizing emissions from different source types EPA is able to ensure timely attainment of the national ambient air quality regulations (NAAQS).
2) These analyses assist in the development of models for predicting pollutant concentrations from source emissions, apportioning sources from air concentration data, and for predicting exposures from different source types. The goal of the aforementioned models is to accurately understand risk and the ways to reduce risks to human health and the environment.
3) Datasets generated by the X-ray fluorescence laboratory cross-cut several laboratories (NERL, NHEERL, NRMRL, etc.) and represent an important collaboration effort. The XRF laboratory products are therefore crucial in the integration of varied, and sometimes wide ranging, agency goals. It is these cross-cutting relationships that enable ORD to collectively assess pollutants which pose the greatest risk to global, regional, state and local populations.
Description:
Radiocarbon analyses of fine particulate matter samples collected during the summer of 2000 in southeast Texas indicate that a substantial fraction of the aerosol carbon at an urban/suburban site (27% to 73%) and at a rural, forested site (44% to 77%) was modern carbon. Data from emission inventories and additional ambient measurements indicate that the most likely sources of this modern carbon are biomass burning fires and biogenic secondary organic aerosol.
Although the research described in this article has been funded in part by the U.S. EPA through cooperative agreement R-82806201, interagency agreement DW13937923 and contract 68-D-00-206, it has not been subjected to the Agency's required peer and policy review and therefore does not necessarily reflect the views of the Agency and no official endorsement should be inferred.